添加元素及含量对Sm-Fe系合金高压气雾化粉体组织及形貌的影响  

Microstructure and Phase Transition of Sm-Fe Alloy High-Pressure Atomized Powder with Adding Elements and Different Components

作　　者：柳昆 王书桓 冯运莉 李晨晓 倪国龙 张一昆 Liu Kun;Wang Shuhuan;Feng Yunli;Li Chenxiao;Zhang Yikun;Ni Guolong(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210

出　　处：《稀有金属》2022年第5期564-571,共8页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(52004097);河北省自然科学基金项目(E2019209597);河北省钢铁联合基金项目(E2021209146);河北省高等学校科学技术研究项目(QN2021115)资助。

摘　　要：采用高压气雾化法制备了化学计量数为Sm_(2)Fe_(17),Sm_(2)Fe_(17)Zr_(0.5)Nb_(0.2)Cu_(0.2)和Sm_(2)Fe_(17)ZrNb_(0.4)Cu_(0.2)的粉体,并利用X射线衍射仪(XRD)、扫描电镜(SEM)及能谱(EDS)元素分析研究了添加元素及含量变化对气雾化粉体粒度、形貌、表面光洁度和微观组织形貌及相组成的影响。结果表明:Sm_(2)Fe_(17)雾化粉体的平均粒径为54μm,内部元素分布不均匀,存在大尺寸的α-Fe相枝晶;XRD结果显示合金主相为2∶17相。随着Zr,Nb和Cu元素的添加及Zr和Nb含量的增加,气雾化合金粉体平均粒度明显降低,粉体表面光洁度提高,粉体内部微观组织均匀性也提高并得到很大程度的细化。Sm_(2)Fe_(17)Zr_(0.5)Nb_(0.2)Cu_(0.2)雾化粉体的平均粒度下降为19μm,内部元素分布均匀,只存在Sm-Fe主相枝晶;随添加Zr,Nb合金元素量的增加,Sm_(2)Fe_(17)ZrNb_(0.4)Cu_(0.2)气雾化合金粉平均粒度仅为13.8μm。部分雾化粉体为核壳结构,呈现0.5μm厚的表层细晶区。XRD结果显示添加Zr,Nb和Cu元素后合金粉末的主相转变为1∶9相,元素的添加促进了亚稳结构的形成。The rare earth permanent magnetic materials have broad application prospects.Block permanent magnetic materials can be obtained by powder forming.The improvement of magnetic properties is closely related to the regulation of microstructure and the quality of the powder.High-quality powder can be prepared by high pressure aerosolization.The powders(Sm_(2)Fe_(17),Sm_(2)Fe_(17)Zr_(0.5)Nb_(0.2)Cu_(0.2)and Sm_(2)Fe_(17)ZrNB_(0.4)Cu_(0.2))were prepared by high-pressure aerosol method.The effects of the addition of elements(Zr/Nb)and content on the morphology,surface finish,microstructure and phase composition of the atomized powders were studied.The powder was prepared in a self-developed high-pressure aerosol equipment,filled with high-purity argon gas,and the pressure was 0.2 MPa.The differential pressure meltΔP=0.4 MPa.The cooling medium at the tightly coupled nozzle was high purity N2 or Ar,and the air injection pressure was 2.5 MPa.X-ray diffractometer(XRD)and scanning electron microscope(SEM)were used to characterize the phase composition and morphology,energy dispersive spectroscopy(EDS)surface scanning was adopted to obtain the element distribution information.The average grain size of Sm2Fe17 powder was~54μm.The internal structure of the powder showed relatively uniform small size dendrites,and some large size dendrites.The large size dendrites wereα-Fe dendrites.The particle size distribution range of Sm_(2)Fe_(17)Zr_(0.5)Nb_(0.2)Cu_(0.2) alloy aerosol powder was significantly narrowed to 5~35μm,and the average particle size of the powder was only 19μm.When the Zr and Nb alloy elements were added to Sm_(2)Fe_(17)ZrNb_(0.4)Cu_(0.2),the maximum powder size was only 35μm,and the average powder size was only 13.8μm.Spherical powders almost disappeared and the surface finish of individual powders was improved.The internal structure of the powder showed the morphology of dendritic crystals.Statistics showed that the primary dendritic crystal size was 0.44μm,the secondary dendritic crystal size was 0.28μm,a

关 键 词：高压气雾化 粉体形貌 核壳结构 表面光洁度 

分 类 号：TG146.4[一般工业技术—材料科学与工程]